A popular device for handling large amounts of information in a data processing system is an automated data cartridge loader (autoloader). Autoloaders store and manage large numbers of data cartridges containing media on which data is recorded. These cartridges are typically tape media, but recently autoloaders have been introduced using hard disk cartridges. One such autoloader is the SCSI Autoloader from Iomega Corporation, which incorporates its exclusive REV® drive and REV® disk cartridges in the autoloader design.
One problem in the field of autoloaders is to increase the storage density while decreasing the equipment storage area required for the autoloaders. Autoloaders are widely accepted because they combine multiple data cartridges and a drive within a single chassis for higher data storage capacity. Typically, prior art autoloaders have an array of storage positions for data cartridges, one or more drives, and some type of automated changer or cartridge transport for picking or gripping a data cartridge and moving the data cartridge between a storage position and the drive. The robotic mechanism, often called a “picker”, is typically mounted to the autoloader chassis relative to the drive in order to move the data cartridges between a storage position and the drive.
A typical picker mechanism automatically exchanges the individual data cartridges between their storage locations and the drive. Different types of data cartridge retrieval/transport mechanisms are used to accommodate the various data cartridge arrangements in different data cartridge library systems. One example of a data cartridge retrieval/transport mechanism utilizes a rotatable robotic arm with an optical sensor for selecting and retrieving the correct data cartridge and transporting the data cartridge to the one or more drives. Another example of a data cartridge retrieval/transport mechanism is a linear robotic mechanism that moves along an X-Y translation or about a pivot in a rotary motion to select, retrieve and transport data cartridges to the one or more drives. The drive is operable to read/write data from or to the media in the data cartridge. A host computer that communicates with a library control unit typically controls operation of the autoloader. In all of these architectures, the data cartridge retrieval/transport mechanism is a complex mechanism which must translate among the multitude of fixed data cartridge storage locations, moving in three dimensions to retrieve selected data cartridges for insertion into the drive. The complexity of this data cartridge retrieval/transport mechanism accounts for a significant component of the cost of the autoloader and requires a significant amount of space to implement.
Therefore, there exists a need in the art of data storage for an autoloader that simplifies the storage and handling of large amounts of information, reduces the size of the system and space required for data storage, while at the same time being cost effective and simple.